The present invention relates to a medical device, namely, an apparatus for delivering compressions to the chest of a patient for treatment and diagnostic purposes.
It has been recognized that applying pneumatic pressure to the thoracic cavity or chest wall of a patient has both diagnostic and treatment applications. For example, chest compressions may be used for airway mucus mobilization in the evaluation and treatment of cystic fibrosis (see, e.g., U.S. Pat. No. 5,453,081, 5,056,505, and 4,838,263), emphysema, asthma, and chronic bronchitis. Chest compressions may be useful for generating mucus samples suitable for detecting lung cancer and other breathing-related conditions. Also, pneumatic pressure may be used in breathing assistance, measuring the concentration of exhaled gases, and determining the condition of airways in patients with respiratory problems. Further, pneumatic chest compression may improve the efficiency, speed, and/or depth of deposition of aerosol medications used in respiratory treatment.
Typically, a bladder or other type of air-receiving chamber is positioned about the thorax or chest of a patient. An airflow generating system is coupled with the bladder by a hose or other connector. The airflow generating system selectively controls the air pressure in the bladder to provide the desired compression(s) of the patient's chest. In prior art systems, the bladder is typically contained within an outer shell in the form of a vest. The vest design positions and holds the bladder in place during the compressions, and is relatively easy for a patient to get in and out of
The typical chest compression vest is designed for long-term use by a single patient. This type of vest allows for limited adjustment, but is generally fitted for a single user. For example, a cystic fibrosis patient may receive daily therapy of chest compressions delivered by a system as described above. Such a system is available from American Biosystems, Inc., St. Paul, Minn., assignee of the present invention. The single-user chest compression vest includes a heavy-duty outer shell made from nylon or other durable fabric. The inner bladder is made from rubber or other suitable material designed to withstand repeated use. In other words, the vest is made from sturdy and durable materials to meet the needs of long-term use.
However, clinical applications for chest compression vests raise different design criteria. In clinical applications, e.g., a respiratory clinic, numerous patients may each need a vest for diagnostic tests and for treatment. Also, in the clinical environment, the vest will likely have some expelled mucus on its outer surface, which may include contagious disease. Consequently, a vest for the clinical environment should be either repeatedly sterilizable or economically viable as a single use product. The long-term vest described above is neither. It cannot be repeatedly sterilized and, due the heavy-duty materials and construction, it is too expensive for single use.
Additionally, once a vest has been used by a patient it should be disposed of as a medical waste product due to the expelled mucus on the vest. Medical waste is commonly burned to destroy any disease or contagious organisms and to reduce the waste to a small size. The vest described above is typically made from materials that do not easily or cleanly burn (e.g., nylon and rubber). Also, these materials may produce harmful particulate or gas emissions when burned.
Consequently, there is a need for a chest compression vest suitable for clinical applications. The vest should meet the unique needs of the clinical environment as described above.